Known vehicle systems use hybrid powertrain architectures to generate at least a portion of required tractive torque originating from a non-hydrocarbon-fueled motor, including an electric machine that transforms electric power to mechanical torque. Powertrain architectures may be configured to transfer tractive torque to an output member through a transmission device. Such powertrain architectures can include series-hybrid configurations, parallel-hybrid configurations, and compound-split hybrid configurations. Electric machines operative as both motors and generators can be controlled to generate torque inputs to the transmission independently of a torque input from the internal combustion engine. The electric machines may react and transform vehicle kinetic energy transmitted through the vehicle driveline to electrical energy that is storable in an electrical energy storage device. A control system monitors various inputs from the vehicle and the operator and provides operational control of the powertrain, including controlling transmission operating range state and gear shifting, controlling the torque-generative devices, and regulating the electrical power interchange among the electrical energy storage device and the electric machines to manage torque and rotational speed outputs of the transmission.
Known electrical circuits for providing electric power to electric machines include a high-voltage DC electrical energy storage device that supplies DC electric power via a high-voltage bus through a DC link to an inverter which transforms the DC electric power to AC electric power to power the electric machine. The electric machine is preferably a multiphase synchronous AC machine including a stator and a rotor magnetically coupled to the stator.